Microwave install...
When I bought my boat, I moved my microwave from my previous boat aboard on a shallow stand I made for it to sit on (first picture). It blocked access to the slider-covered storage areas behind it and had limited use of space underneath it.
I modified the shelf by attaching two cut-off bannister posts as legs and afixed the rear of the microwave stand to the shelf rail above the sliders (second picture). That permitted access to storage sliders, and the dish pan/drying rack slid under the new stand, freeing up counter space.